1. The Krebs Cycle & Electron Transport
Chapter 9.2

2. Krebs Cycle (aka Citric Acid Cycle)
Aerobic part of cellular respiration, it requires oxygen
The process of breaking pyruvic acid into carbon dioxide (CO2) using oxygen (O2)
This process releases energy

3. Takes place in mitochondrion
Pyruvic acid (3C) from glycolysis is broken down to CO2 (leaves 2C) & electrons are removed to change NAD+ to NADH
Acetyl-CoA (2C) + 4 C = citric acid (6C)

4. Citric acid (6 C) is broken down to 5C and then to 4C (CO2 & NADH formed each time)
1 ATP & 1 FADH2 are also formed
4 NADH formed

6. Electron Transport Chain
ETC uses the high energy electrons from the Krebs Cycle to convert ADP into ATP
ETC composed of carrier proteins in the inner membrane of the mitochondrion

7. At the end of ETC is an enzyme that combines e- from the ETC with H & O to form water
Oxygen serves as final e- acceptor of the ETC

8. 2 e- moving down the ETC transports H+ across the membrane; charge differential is created and used to form ATP

9. Most of the ATP produced during cellular respiration is made during the Electron Transport Chain

11. Totals Glycolysis = 2 ATP Krebs cycle = 2 ATP
electron transport = 32 ATP
Total ATP

12. Video: http://www. copernicusproject. ucr. edu/ssi/HSBiologyResources
Video: Glycolysis and Cellular Respiration